Going Electric with my 996!
04-13-2014, 03:17 PM
#166
Banned
Thread Starter
Got a surprise today... the grad student I had helping do some programming just got a spring/summer internship at Tesla! Great for him... not so great for me. Although much of the harder programming is done, there is still much fine-tuning etc. to finish up. He says he can remotely continue to update things, but I'm not sold 100% on the idea. We could put the car back together and I could probably drive around just fine using the stereo head-unit for all the necessary data, but it would be a big bummer to not have everything appear stock and function in the gauge cluster... most items ARE working, speedo is good, many lights, but still don't have RPM and a few others. Just another bump in the road for this build I guess - It's taken 1.5 years... why not have it go longer?
In other news, I've got the old 18" Turbo Twist wheels and new(ish) tires for sale... wheels aren't in great cosmetic shape - but if you want a commemorative collectible from this project - here's an opportunity! Link here: https://rennlist.com/forums/parts-ma...l#post11285020
In other news, I've got the old 18" Turbo Twist wheels and new(ish) tires for sale... wheels aren't in great cosmetic shape - but if you want a commemorative collectible from this project - here's an opportunity! Link here: https://rennlist.com/forums/parts-ma...l#post11285020
05-03-2014, 05:26 AM
#167
Banned
Thread Starter
OK, so it was kinda slow for the past two weeks... not much interesting when you're just trying to get things working perfectly, making small adjustments and continuing tweaks in programming... BUT the good news is we've got the power turned up to 1500 amps now, so that's 75% power and we're hoping to turn it up to 11 (ok, maybe just 10... or 9) after more testing. Performance should be impressive...
One thing you'll find with instant torque is that the motor and transaxle want to twist when the throttle is snapped on quickly... photo below is the new brace that prevents rotation but still allows movement up/down/left/right without transmitting vibration into the chassis.
As I replaced my old leaking struts and got the sport techno wheels on... car looks great, stanced even. When you add new clean bits, you want to pretty others up before they go back on... below is a photo of some suspension brace parts getting paint prior to reassembly.
Finally, a simple 12V battery switch that can be used for service and long term storage (not that I plan on storing her when complete - gotta make up for almost 2 years of not driving!).
Ah, one more thing that I don't have pictured, but makes a HUGE difference... we've isolated the vibration from the power steering pump, an electric one from an MR2. Sucker was LOUD, and now is tame. That was certainly one problem I didn't plan on from the outset. The fun part is I can easily turn power steering pressure up and down now, so it can be adjusted for different driving types. That said, my goal is to make the car drive as if it were stock, so that will be how I try to tune it now.
One thing you'll find with instant torque is that the motor and transaxle want to twist when the throttle is snapped on quickly... photo below is the new brace that prevents rotation but still allows movement up/down/left/right without transmitting vibration into the chassis.
As I replaced my old leaking struts and got the sport techno wheels on... car looks great, stanced even. When you add new clean bits, you want to pretty others up before they go back on... below is a photo of some suspension brace parts getting paint prior to reassembly.
Finally, a simple 12V battery switch that can be used for service and long term storage (not that I plan on storing her when complete - gotta make up for almost 2 years of not driving!).
Ah, one more thing that I don't have pictured, but makes a HUGE difference... we've isolated the vibration from the power steering pump, an electric one from an MR2. Sucker was LOUD, and now is tame. That was certainly one problem I didn't plan on from the outset. The fun part is I can easily turn power steering pressure up and down now, so it can be adjusted for different driving types. That said, my goal is to make the car drive as if it were stock, so that will be how I try to tune it now.
05-03-2014, 12:26 PM
#168
Rennlist Member
Getting closer to "completion"! (Is a project like this ever truly finished?)
Maybe I missed it, but can you elaborate a little more on the electric power steering pump (what year MR2 it came from, where you mounted it, etc.)?
Maybe I missed it, but can you elaborate a little more on the electric power steering pump (what year MR2 it came from, where you mounted it, etc.)?
05-05-2014, 10:05 PM
#169
Banned
Thread Starter
I'll try to get some photos. Thanks for the question... and you are correct... we'll probably never be done, but I sure hope to get to the done enough part soon!
06-02-2014, 02:35 AM
#170
Banned
Thread Starter
Well, with all the "major" things done, the little things just seem to take longer and longer... but we're making progress and I wanted to make a small update. It's been almost a month since my last!
The car is now drivable, however not ready for prime-time... the gage cluster is still out as we try to get all the final bits working. Late last week, testing began with the power somewhat turned up. This testing “work” is in identifying what self-protection features are preventing the high power acceleration for more than a brief moment, then checking to see if it’s appropriate to widen up those parameters. So it’s a cyclic process of confidently identifying, adjusting and testing over and over again. So far, It’s up to about 1200 motor amps peak. That’s an intense few seconds. Looking forward to the upcoming week of testing!
Outisde of this testing, some of the items yet to be completed:
- Install a "valet switch" to reduce power for those that don't need everything she's got (stock defrost toggle with LED indicator, to be installed in blank spaces to the left of stereo head unit in center console)
- Get Tach and Temperature gages working
- Get new Air Conditioning pump plumbing completed
- When air conditioning is on, cause both front radiator fans to be on “low” speed
- Lots of labeling and interior reassembling
Something else that has taken MUCH longer than anticipated... balancing the battery cells. Typically, the individual cells in a battery have somewhat different capacities and may be at different levels of state of charge. Without redistribution, discharging must stop when the cell with the lowest capacity is empty (even though other cells are still not empty). Without balancing, the cell of smallest capacity is a “weak point”, it can be easily overcharged or over-discharged while cells with higher capacity undergo only partial cycle.
Apparently, we didn't finish balancing the batteries when first received. So by not finishing that a little over a year ago, they became more out of balance than how they were received from the factory. We're top balancing (rather than bottom balancing), which basically means we do our best to charge all batteries until some register as full, then partially discharge the full ones, and charge again. It sounds simple, but to actually get all the batteries perfectly balanced, it has taken many, many cycles. Glad to have it finished, meaning we could then turn up the power and start testing, as described above.
The car is now drivable, however not ready for prime-time... the gage cluster is still out as we try to get all the final bits working. Late last week, testing began with the power somewhat turned up. This testing “work” is in identifying what self-protection features are preventing the high power acceleration for more than a brief moment, then checking to see if it’s appropriate to widen up those parameters. So it’s a cyclic process of confidently identifying, adjusting and testing over and over again. So far, It’s up to about 1200 motor amps peak. That’s an intense few seconds. Looking forward to the upcoming week of testing!
Outisde of this testing, some of the items yet to be completed:
- Install a "valet switch" to reduce power for those that don't need everything she's got (stock defrost toggle with LED indicator, to be installed in blank spaces to the left of stereo head unit in center console)
- Get Tach and Temperature gages working
- Get new Air Conditioning pump plumbing completed
- When air conditioning is on, cause both front radiator fans to be on “low” speed
- Lots of labeling and interior reassembling
Something else that has taken MUCH longer than anticipated... balancing the battery cells. Typically, the individual cells in a battery have somewhat different capacities and may be at different levels of state of charge. Without redistribution, discharging must stop when the cell with the lowest capacity is empty (even though other cells are still not empty). Without balancing, the cell of smallest capacity is a “weak point”, it can be easily overcharged or over-discharged while cells with higher capacity undergo only partial cycle.
Apparently, we didn't finish balancing the batteries when first received. So by not finishing that a little over a year ago, they became more out of balance than how they were received from the factory. We're top balancing (rather than bottom balancing), which basically means we do our best to charge all batteries until some register as full, then partially discharge the full ones, and charge again. It sounds simple, but to actually get all the batteries perfectly balanced, it has taken many, many cycles. Glad to have it finished, meaning we could then turn up the power and start testing, as described above.
06-24-2014, 06:44 AM
#171
Banned
Thread Starter
I'm well overdue for an update, and I finally have a few items worth reporting. Back in April I lost the grad student who was helping program the CAN bus controllers to talk to the factory gages to a Summer/Fall internship at Tesla... great for him, but not so great for my project. Now, the good news... Kirk at ShiftEV, who is heading up this project, called in the big guns. I am extremely excited and thankful to say that Otmar Ebenhoech (father of the Zilla motor controller, which we are using in this car) and Debbie Hollenback from the local EV Club (who is probably another super-star in the making) have come to the rescue!
Debbie is doing the programming and Otmar is in charge of the hardware and project design. In, what he calls "typical engineer" fashion, Otmar began by ripping out all the off-the-shelf components wired in previously and opted for a new "bleeding edge" system that was far smaller and more powerful. The great thing about their participation is that it is a win-win: they haven't integrated a system like this to work the stepper motors in the dash before, so their efforts here will assist with other future projects they have planned.
Speaking of other projects... if you haven't heard anything about Otmar's Stretchla project, you best watch the video below and review his amazing stretched VW Westfalia to Tesla conversion story.
Back to my project... As has been the story all along, the devil is in the details, and the details continue to take time. The latest update in regards to the programming for the dash was received as follows: "Today we spent the hours realizing that our method of zeroing the gauges was not consistently accurate. After learning some more stepper motor theory and studying the guts of the stepper motor driver libraries we came up with a way to reset the needles on startup that guarantees them starting from exactly zero. Deb wrote up the test code and we found it to be robust. It feels like we are almost done, as is has felt every day for weeks :-) We'll be on it again tomorrow."
Progress is being made, slowly but surely! The beautiful summer days are well upon us here in Oregon... I think I'll have the car back before they end... here's hoping!
Debbie is doing the programming and Otmar is in charge of the hardware and project design. In, what he calls "typical engineer" fashion, Otmar began by ripping out all the off-the-shelf components wired in previously and opted for a new "bleeding edge" system that was far smaller and more powerful. The great thing about their participation is that it is a win-win: they haven't integrated a system like this to work the stepper motors in the dash before, so their efforts here will assist with other future projects they have planned.
Speaking of other projects... if you haven't heard anything about Otmar's Stretchla project, you best watch the video below and review his amazing stretched VW Westfalia to Tesla conversion story.
Back to my project... As has been the story all along, the devil is in the details, and the details continue to take time. The latest update in regards to the programming for the dash was received as follows: "Today we spent the hours realizing that our method of zeroing the gauges was not consistently accurate. After learning some more stepper motor theory and studying the guts of the stepper motor driver libraries we came up with a way to reset the needles on startup that guarantees them starting from exactly zero. Deb wrote up the test code and we found it to be robust. It feels like we are almost done, as is has felt every day for weeks :-) We'll be on it again tomorrow."
Progress is being made, slowly but surely! The beautiful summer days are well upon us here in Oregon... I think I'll have the car back before they end... here's hoping!
Last edited by rustymon; 06-24-2014 at 02:21 PM.
06-24-2014, 08:06 AM
#172
As much as I love the Porsche engine sound I love seeing your progress and am slightly jealous...although I would personally do a Coupe. If electrics were within my budget I'd get a rolling 944 and convert it for a daily driver. Fantastic job!
Chris
Chris
06-30-2014, 12:06 AM
#174
Banned
Thread Starter
Thanks for the vote of confidence, Chris. I have become addicted to driving with the top down, so it had to be a convertible for me. Yes, a coupe would have weighed less and may have yielded some extra space for batteries or components, but although I am definitely into the performance side of things, I wanted something that was more of my dream car than a rational car... and imagine how pleasant driving a quiet electric car will be, flying down the road!
06-30-2014, 12:52 AM
#175
Banned
Thread Starter
Some more updates... We had one heck of a problem getting the tachometer working... first issue turned out to be a blown "Hair ball" board for our Zilla motor controller. We weren't sure how that happened, however when the replacement arrived, we discovered that although the correct COLOR wire was hooked up, it was really one of TWO with that color, and the wrong one! That could have been the reason the Hair ball board got fried... so several hours were spent tracking all wires and labeling things, just to make sure we didn't make the same mistake again with another wire.
Otmar and Deb have the gage cluster ready for in-car testing, however we need to add a couple of LED's before we wire it in. I'm excited about the slick way they are able to display battery temperature on the oil pressure gage with no additional wiring, just taking the CAN bus signal from our Battery Management System (BMS) data.
Some more good news... Kirk measured energy consumption at 310W/h per mile at a 65 MPH cruise on the way back to the shop from Otmar's garage... this should mean VERY conservative range estimates between 83 and 93 miles... so 100 isn't out of the question on a long continuous and gentle drive. Not making any promises here, but if I can go further than my wife in her Nissan Leaf, I think we'll know which car we're taking for rides to the coast!
Now, one of the little bits I'm very excited about... the valet switch! As you can see in the photo below, it is an instant push button toggle (top left button, round/silver) with a blue ring that illuminates when in high power mode. It's toggle circuit was added to the same arduino board that will control the car's heater. A little code and some final connections, then we can test this out! The idea is this... you get 100% power when on, but when off, you're limited to a calm-Sunday-drive/economy setting of about 20% power or something like that... maybe I'll call it the "wife switch!"
Otmar and Deb have the gage cluster ready for in-car testing, however we need to add a couple of LED's before we wire it in. I'm excited about the slick way they are able to display battery temperature on the oil pressure gage with no additional wiring, just taking the CAN bus signal from our Battery Management System (BMS) data.
Some more good news... Kirk measured energy consumption at 310W/h per mile at a 65 MPH cruise on the way back to the shop from Otmar's garage... this should mean VERY conservative range estimates between 83 and 93 miles... so 100 isn't out of the question on a long continuous and gentle drive. Not making any promises here, but if I can go further than my wife in her Nissan Leaf, I think we'll know which car we're taking for rides to the coast!
Now, one of the little bits I'm very excited about... the valet switch! As you can see in the photo below, it is an instant push button toggle (top left button, round/silver) with a blue ring that illuminates when in high power mode. It's toggle circuit was added to the same arduino board that will control the car's heater. A little code and some final connections, then we can test this out! The idea is this... you get 100% power when on, but when off, you're limited to a calm-Sunday-drive/economy setting of about 20% power or something like that... maybe I'll call it the "wife switch!"
Last edited by rustymon; 07-18-2014 at 04:49 PM.
07-11-2014, 03:45 PM
#178
Banned
Thread Starter
A mini-update... Tuesday was spent finishing the car-side wiring & connectors for the heater control circuit (also the Valet mode circuit). Most of this was under the dash, and some in the back. Otmar finished the circuit assembly and it’s code. We plugged it in and ran it all prior to mounting the enclosure box and switch panel. We had one minor connection to fix, and a code change that took less than a minute. Then it was working flawlessly. Other than mounting the box under the dash, that’s done. Today, the gage cluster is ready for in-car testing and we'll be wiring it to the car so we can get to it. I’ll keep you posted...
Here is a photo of the "valet switch" (AKA the anti-stability management button - thanks tokyopav!) with the light on. Also shows an added defrost button below the silver button for something less risky if poked. We're only driving its LED to indicate the high voltage heater circuit is powered. Pushing its toggle has no result. This seemed better than an extra hole for a new LED anywhere else, as we had originally planned on inserting an LED in a vent or something - this is MUCH cleaner.
TBH, I'm going back & forth on the use of the silver button for the valet switch... I was going to use another stock button but others on the build brought up the concern that it might easily be hit on accident while driving and cause an accident. It looks pretty good, but isn't stock... any comments or feedback here? Should I go with a stock button instead?
I'm not sure if I described the heating system previously... but as we no longer have an ICE to generate heat, we have installed 3 high-speed electric water heaters which should do the job very nicely and may even heat up the interior faster than the engine did. See the last photo for a view of them when they were installed... 9 months ago! Ugh... getting closer... really want to drive in this great summer weather!
Here is a photo of the "valet switch" (AKA the anti-stability management button - thanks tokyopav!) with the light on. Also shows an added defrost button below the silver button for something less risky if poked. We're only driving its LED to indicate the high voltage heater circuit is powered. Pushing its toggle has no result. This seemed better than an extra hole for a new LED anywhere else, as we had originally planned on inserting an LED in a vent or something - this is MUCH cleaner.
TBH, I'm going back & forth on the use of the silver button for the valet switch... I was going to use another stock button but others on the build brought up the concern that it might easily be hit on accident while driving and cause an accident. It looks pretty good, but isn't stock... any comments or feedback here? Should I go with a stock button instead?
I'm not sure if I described the heating system previously... but as we no longer have an ICE to generate heat, we have installed 3 high-speed electric water heaters which should do the job very nicely and may even heat up the interior faster than the engine did. See the last photo for a view of them when they were installed... 9 months ago! Ugh... getting closer... really want to drive in this great summer weather!
07-15-2014, 03:49 AM
#179
Banned
Thread Starter
A few bits of progress and a major milestone...
The pics show an attempt to alter an unused yellow indicator to a green with black arrow. Didn't look quite as good as hoped, so we replaced the former tach-red-line red LED with a green LED for this indicator instead. Lots of other small wiring & tidying up too... which leads to the big news...
The gages are IN... and they WORK! Some arduino enclosures to finish up and various wires to tie under the dash, but basically the system is all together and we can really focus on DRIVE TESTING now! Very excited...
Just noticed that this is my 200th post on the board... glad to finally (kinda) get to drive the thing. Still lots to test/tweak so we can slowly turn up the power...
The pics show an attempt to alter an unused yellow indicator to a green with black arrow. Didn't look quite as good as hoped, so we replaced the former tach-red-line red LED with a green LED for this indicator instead. Lots of other small wiring & tidying up too... which leads to the big news...
The gages are IN... and they WORK! Some arduino enclosures to finish up and various wires to tie under the dash, but basically the system is all together and we can really focus on DRIVE TESTING now! Very excited...
Just noticed that this is my 200th post on the board... glad to finally (kinda) get to drive the thing. Still lots to test/tweak so we can slowly turn up the power...
07-15-2014, 10:47 AM
#180
Congrats again. You can do do many things with Arduino's and hence the reason why I suggested using one for the automatic emergency power cutoff but I see that you used it in other ways. It's looking like a high class ev build. 